Holes in the map, part 1: Beavers

In the first installment of a new series about species missing from the Lake District, Site Manager Lee Schofield introduces us to the Eurasian Beaver

As a nation surrounded by the sea, there is no scope for some of our missing species to return to Britain under their own steam, no matter how attractive we manage to make our countryside.

The Eurasian beaver, hunted to extinction in the UK about 400 years ago, is one such species. As well as being good eating, beavers were valued for their castoreum, a scent gland that provided us with an ingredient used in perfumes (eau de beavoir anyone?) But beaver fur, which is incredibly warm and soft, was the real prize and drove a multinational killing spree that lasted for generations. Slowly, beaver fever took its inevitable toll, and both Eurasian and North American beaver populations came close to being wiped out before society lost its appetite.

Today we live in a more enlightened age and over the course of the last few decades beavers have made an astonishing comeback. Released from the pressure of hunting, the few remaining European and American populations that survived have rapidly spread, recolonizing huge areas. We’ve helped speed things along with an ever-increasing number of reintroductions.

In Cumbria, as in many other parts of the UK, beavers disappeared a very long time ago but there is enough historical evidence for us to be sure that they were part of our local fauna. Thanks to the efforts of the Cumbria Beaver Group they are about to make their return. This partnership of nature conservation organisations and private landowners, with advice from government bodies is working hard to see beavers returned to Cumbria.

The first steps are to establish a number of enclosed beaver release sites, with the first one being sited on the Lowther Estate near Askham. These trial sites will allow the beavers to be closely monitored and be used to demonstrate the impacts that beavers could have on the wider landscape to the local community. From there, if there is sufficient support, beavers will hopefully be able to live wild in Cumbria once again.

Beavers are Europe’s largest rodent. They are shy and secretive, mostly nocturnal, brown and dumpy, messy and irascible. On the face of it, they don’t seem like the most obvious candidate for restoration. But reintroducing beavers is not about what they are, it’s about what they do.

Beavers are often referred to as ecosystem engineers. The impact that they have on their habitat, and on the many other species that share it with them, is phenomenal.

Our landscapes today are characterised by tidiness. Our rivers have been straightened, our scrub removed, boggy areas drained, vast acreages have been turned into sterile monocultures. This is not how nature should be. Our obsession with neatness, coupled with our drive to turn every last corner of land over to production is a big part of why wildlife is leaching out of our countryside at an alarming speed. Beavers, given the chance, can go a long way to undoing this. They have an incredible ability to bring chaos.

Beavers, being slow and meaty, make an attractive meal for pretty well all of the northern hemisphere’s top predators. On the ground, they are slow and cumbersome, and although they possess seriously impressive teeth they’re not much use in self-defence. Give them some open water, though, and they are swift and sleek, capable of escaping wolves, bear and lynx, which they evolved alongside, with ease. And so, over millions of years, beavers have developed the skills to engineer as much open water as they can; wetlands are the key to their survival.

The main way that beavers create wetlands is by damming. Their powerful teeth are nature’s chainsaws. Gnawing through the base of trees to fell them brings their canopies down to ground level. The soft inner bark and leaves provide the bulk of the beavers’ diet with the sturdier branches, and a generous helping of mud, act as their bricks and mortar. As any child that has messed around in a stream knows, properly stopping the flow of water is not easy. Beavers are masters at it, constantly tweaking and improving, plugging dam gaps where they spring, to keep the pools that develop behind them deep and safe.

Although beavers obviously aren’t consciously altruistic, a huge suite of other wetland species benefit from their efforts. Amphibians, dragonflies and many other invertebrates, fish and birds boom once beavers get going. They also bring lots of direct benefits to us. Because beaver created wetlands are so complex and chaotic, water moves through them very slowly, which not only helps to improve the water’s quality, but also reduces the risk of flooding for people living downstream.

A common misconception about beavers, for which CS Lewis and his Narnian beavers are partly to blame, is that they eat fish. They don’t. They are completely herbivorous. The complex habitats that beavers create typically support healthy insect life, and so fish, particularly brown trout, thrive and grow larger where beavers are present. In the USA, beavers have been used as a conservation tool to restore rivers for fish, often with incredible success.

But there can be downsides to living with beavers too, such as if they colonise the wrong place – modified lowland agricultural areas for example, where dammed ditches might cause localised flooding. Their incredible ability to cut down trees is another characteristic that can bother people, but like everything, it’s not quite as straightforward as it seems. Most of our native tree species regrow after being felled, so beavers cutting them down doesn’t kill them and can, in fact, promote better woodland structure by producing more in the way of young, scrubby growth which is often better habitat than woodlands containing only big mature trees. 

Interestingly, the UK is massively behind the curve with regard to beavers. Almost every country in Europe now has beavers back again and collectively these nations have learned everything there is to know about how best to deal with them. Lots of work has already been done in the UK to benefit from these other European experiences, and there is even a Beaver Management Handbook, full of practical guidance as to how to mitigate and manage the impacts of even the most challenging beaver related issues.

If beavers are allowed to return permanently to the Lake District, what changes might we expect? Beavers can’t dam across fast flowing rivers, and they can’t hold water in steep terrain, so the areas that they will focus their energies on will be those that are already likely to be wet and probably marshy.

Beavers offer a fantastic opportunity to turn those bits of the landscape that farmers have battled to drain and improve, but have stayed resolutely soggy and rushy, into something much more special. It’s these places, and around the edges of existing waterbodies and bogs, that beavers should be allowed to work their magic. In some situations, farmers and landowners could even be paid to give these places over to nature. With sensible management strategies in place to deal with beavers in the wrong places, and a degree of compromise, I’m confident that we could live alongside beavers once again, with spectacular results for our wildlife as a whole.

For information on the Cumbria beaver group, visit www.cumbriabeavers.org.uk or on Twitter @CumbriaBeavers
To contact Cumbria Beaver Group, email info@cumbriabeavers.org.uk